Windows based lighting calculator. This is a very handy tool for lighting designers and VJ's that spec or rig systems.

Created by an industry pro Paul Pelletier, who very kindly shares this great little app. Has a large database of professional lighting fixtures with photometric data, Elecreical calculations including ohms law volt/amps/watts, volt drop for long cable runs, power load, load distribution when using multiple rigging points and more.